# NTSB ATL95LA172: Grumman G-164A, N9700, Lynchburg, SC, September 22, 1995 - Type: NTSB accident investigation - Classification: Accident · No injuries · Limited investigation · Final report - Date: September 22, 1995, 10:30 local (14:30 UTC) - Place: Lynchburg, SC - Coordinates: 34.050224, -80.069602 (estimated) - Nearby events: https://openairdocs.org/map.md?lat=34.0502&lon=-80.0696&mi=10 - Phase of flight: [Enroute](https://openairdocs.org/ntsb-phases/400) (OpenAirDocs' grouping) - Highest injury: No injuries - Injuries: 1 uninjured - Status: Completed, report April 29, 1996 - Report: Approved by Office Director - NTSB case key (mKey): 3628 - NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=ATL95LA172 - NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/3628/pdf - Page: https://openairdocs.org/ntsb/ATL95LA172 ## Probable cause The failure of the magneto mount pad, which resulted in a malfunction of the magneto timing and partial loss of engine power. A factor relating to the accident was: high vegetation in the emergency landing area. ## Sequence of events In NTSB's coding before 2008 (https://www.ntsb.gov/GILS/Documents/codman.pdf). - Loss of engine power(partial) - mech failure/malf, cruise - ignition system,magneto - failure (cause) - Forced landing, emergency descent/landing - Nose over, emergency landing - terrain condition - crop (contributing factor) ## Analysis During cruise flight, while the pilot was returning from spraying a field, the engine began running roughly. The pilot stated he checked both magnetos, and then the engine lost power. He attempted to restart the engine, but was unable to do so. He elected to land in a soybean field. During the flare, the landing gear was caught by the 5 foot high soybean crop, and the aircraft nosed over. Postcrash examination showed that the right magneto timing had been lost, because the rear attachment base had broken, permitting the magneto to shift. ## Factual narrative On September 22, 1995, about 1030 eastern daylight time, a Grumman G164A, N9700, nosed over during a forced landing near Lynchburg, South Carolina. The airplane was operated by Sky Ag Aviation, under the provisions of 14 CFR Part 91, and visual flight rules. Visual meteorological conditions prevailed. A flight plan was not filed for the ferry flight. There were no injuries to the commercial pilot, and the airplane was substantially damaged. Origination of the flight was at approximately 1000, from Lynchburg, South Carolina. The pilot stated that during the ferry flight from spraying a field, the engine began running roughly. He checked the magnetos with no improvement in the roughness. The pilot then added power, and the roughness increased, resulting in a forced landing in a soybean field. During the landing roll the airplane nosed over. Post accident investigation displayed that the engine would not start with the magnetos turned to the both position. With the magneto switch placed in the left position, the engine started and ran steadily. Further investigation disclosed that the left rear attachment bolt for the right magneto was missing, and the safety wire was broken. The right rear corner of the magneto was broken, allowing the magneto to shift enough to jump the teeth of the magneto to the engine drive coupling. This resulted in a loss of engine to magneto timing. The fracture faces of the broken magneto mount were dirty and fretted, except for one small area: indicative of a pre-existing fracture. ## Aircraft - Registration: [N9700](https://openairdocs.org/deregistered/N9700-1999-07-21), registration cancelled 1999-07-21, S/N 1232 (OpenAirDocs) - Reported make and model: GRUMMAN G-164A - Registry model: [Grumman Acft ENG Cor-Schweizer G-164A](https://openairdocs.org/model/grumman-acft-eng-cor-schweizer-g-164a) (registry code 3952801) (OpenAirDocs) - Category: Airplane - Serial number: 1232 - Airframe hours: 3770 - Engines: P&W R-985 450 horsepower reciprocating - Damage: Substantial damage - Flight: Positioning, Part 91 - Registered owner: Sky Ag Aviation - Airworthiness certificate: Special, Restricted (Special) - Last inspection: Annual, December 1, 1994, 488 hours before - Departed: PVT, TALLON FIELD, SC ## Flight crew As NTSB recorded them. NTSB leaves out names. - Pilot; age 48; commercial; airplane ratings: multi-engine land, single-engine land; instrument ratings: airplane; medical: class 2, valid medical--w/ waivers/lim; seat: front; flight hours: 10,000 total, 2,000 in this make and model, 10,000 as pilot in command, 100 in the last 90 days, 50 in the last 30 days, 6 in the last 24 hours ## Weather - Conditions: Visual (VMC), Day - Wind: 160° at 6 knots - Visibility: 3 statute miles - Lowest ceiling: 700 ft broken - Temperature: 75 °F, dew point 75 °F - Altimeter: 30.00 inHg - Observed at: SSC, 15 nm away ## FAA reports on this event (1) The FAA's own accident and incident reports, matched to the aircraft by N-number and date (OpenAirDocs). - [Accident 19950922030119A](https://openairdocs.org/incident/19950922030119A), Sep 22, 1995: Scwzer G164A, Lynchburg, SC, Substantial damage. Lost power on low level ferry flight. Nosed over landing. Loose right magneto. Safety wire broke. Lost engine timing ## Other investigations on N9700 (1) From the NTSB's public API. Aircraft are matched to registry aircraft by N-number and event date, checked against the reported serial number, make and model; the registry's history has gaps, so older matches can be wrong. Compare the reported make and model. - [NTSB FTW74FRD48](https://openairdocs.org/ntsb/FTW74FRD48), Jun 10, 1974: Grumman G-164A (N9700), Kaplan, LA, substantial damage From the NTSB's public API. Aircraft are matched to registry aircraft by N-number and event date, checked against the reported serial number, make and model; the registry's history has gaps, so older matches can be wrong. Compare the reported make and model. --- OpenAirDocs.org is an independent research project of [Contrail Labs](https://contraillabs.com/). It is not affiliated with the FAA or the NTSB. Source documents are U.S. government works in the public domain.